CVE-2024-42109

MEDIUM EPSS 15.0%
Published Jul 30, 20241y ago · Modified Jun 17, 20262w ago
5.5 CVSS 3.1
Medium
Find Similar
Published Jul 30, 2024 1y ago
Last Modified Jun 17, 2026 2w ago

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: unconditionally flush pending work before notifier syzbot reports: KASAN: slab-uaf in nft_ctx_update include/net/netfilter/nf_tables.h:1831 KASAN: slab-uaf in nft_commit_release net/netfilter/nf_tables_api.c:9530 KASAN: slab-uaf int nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597 Read of size 2 at addr ffff88802b0051c4 by task kworker/1:1/45 [..] Workqueue: events nf_tables_trans_destroy_work Call Trace: nft_ctx_update include/net/netfilter/nf_tables.h:1831 [inline] nft_commit_release net/netfilter/nf_tables_api.c:9530 [inline] nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597 Problem is that the notifier does a conditional flush, but its possible that the table-to-be-removed is still referenced by transactions being processed by the worker, so we need to flush unconditionally. We could make the flush_work depend on whether we found a table to delete in nf-next to avoid the flush for most cases. AFAICS this problem is only exposed in nf-next, with commit e169285f8c56 ("netfilter: nf_tables: do not store nft_ctx in transaction objects"), with this commit applied there is an unconditional fetch of table->family which is whats triggering the above splat.

CVSS Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
15.0% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Affected Products 4

VendorProductVersionRange
linuxlinux_kernel*≥5.15.129  –  <5.15.163
linuxlinux_kernel*≥6.1.50  –  <6.1.98
linuxlinux_kernel*≥6.5  –  <6.6.39
linuxlinux_kernel*≥6.7  –  <6.9.9

References 6

  • git.kernel.org https://git.kernel.org/stable/c/09e650c3a3a7d804430260510534ccbf71c75b2e
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/3325628cb36b7f216c5716e7b5124d9dc81199e4
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/4c06c13317b9a08decedcd7aaf706691e336277c
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/55a40406aac555defe9bdd0adec9508116ce7cb1
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/9f6958ba2e902f9820c594869bd710ba74b7c4c0
    Patch
  • lists.debian.org https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/09e650c3a3a7d804430260510534ccbf71c75b2e
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/3325628cb36b7f216c5716e7b5124d9dc81199e4
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/4c06c13317b9a08decedcd7aaf706691e336277c
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/55a40406aac555defe9bdd0adec9508116ce7cb1
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/9f6958ba2e902f9820c594869bd710ba74b7c4c0
    Patch